writes "This just-released research report, Load Testing a Virtual Web Application, looks at the effects of virtualization on a typical ASP Web application, using VMWare on Linux to host a Windows OS and IIS web server. While virtualizing the server made it easier to manage, the number of users the virtualized Web app could handle dropped by 43%. The article also shows interesting graphs of how hyper-threading affected the performance of IIS."
The report urges readers to take this research as a data point. No optimization was done on host or guest OS parameters.